Working vehicle

ABSTRACT

To reduce complexity of operation when a working vehicle performs automatic steering, the working vehicle includes a vehicle body to be manually steered with a steering wheel or automatically steered to travel forward or rearward, an operator&#39;s seat on the vehicle body, a console located forward of the operator&#39;s seat or located on one side of the operator&#39;s seat, a first manual operator for automatic steering provided in or on the console, and a second manual operator for automatic steering attachable at a location rearward of the operator&#39;s seat.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of InternationalApplication No. PCT/JP2021/047618, filed on Dec. 22, 2021, which claimsthe benefit of priority to Japanese Patent Application No. 2020-219798,filed on Dec. 29, 2020. The entire contents of each of theseapplications are hereby incorporated herein by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to, for example, a working vehicle such asa tractor.

2. Description of the Related Art

A working vehicle disclosed in Japanese Unexamined Patent ApplicationPublication No. 2020-1467 is known. The working vehicle of JapaneseUnexamined Patent Application Publication No. 2020-1467 includes amanual operator (correction switch) for automatic steering that isoperable when it is attached to a console and that can be detached fromthe console, moved to a location rearward of the operator's seat, andthen operated at that location.

SUMMARY OF THE INVENTION

With regard to the working vehicle of Japanese Unexamined PatentApplication Publication No. 2020-1467, when automatic steering isperformed, the operator moves the manual operator (correction switch)for automatic steering according to the direction of travel of thevehicle body. This moving action is sometimes complicated.

Preferred embodiments of the present invention make it possible toreduce complexity of operation when automatic steering of the workingvehicle is performed.

Technical solutions according to preferred embodiments of the presentinvention are as follows.

A working vehicle according to an aspect of a preferred embodiment ofthe present invention includes a vehicle body to be manually steeredwith a steering wheel or automatically steered to travel forward orrearward, an operator's seat on the vehicle body a console locatedforward of the operator's seat or located on one side of the operator'sseat, a first manual operator for automatic steering provided in or onthe console, and a second manual operator for automatic steeringattachable at a location rearward of the operator's seat.

In an aspect of a preferred embodiment of the present invention, thefirst manual operator and the second manual operator may includerespective steering switches to be operated to issue an instruction tostart or stop the automatic steering.

In an aspect of a preferred embodiment of the present invention, theworking vehicle may further include a position detector to detect aposition of the vehicle body. The first manual operator may include afirst defining switch to be operated to issue an instruction to define areference travel line based on which the automatic steering isperformed, and a first correction switch to be operated to issue aninstruction to correct the position of the vehicle body detected by theposition detector, or the first manual operator and the second manualoperator may include respective defining switches to be operated toissue an instruction to define a reference travel line based on whichthe automatic steering is performed, and respective correction switchesto be operated to issue an instruction to correct the position of thevehicle body detected by the position detector.

In an aspect of a preferred embodiment of the present invention, theworking vehicle may further include a controller to control theautomatic steering. The controller may be configured or programmed todefine, upon operation of the first defining switch or one of therespective defining switches at a start and end of travel of the vehiclebody in which the vehicle body is manually steered, the reference travelline based on positions of the vehicle body detected by the positiondetector, start the automatic steering upon operation of one of therespective steering switches to start the automatic steering, stop theautomatic steering upon operation of one of the respective steeringswitches to stop the automatic steering, correct a position of thevehicle body upon operation of the first correction switch or one of therespective correction switches, and upon operation of one of therespective switches of the first manual operator and the second manualoperator having a same function, disable another of the respectiveswitches of the first manual operator and the second manual operatoruntil the automatic steering ends.

In an aspect of a preferred embodiment of the present invention, thesecond manual operator may be electrically connected to the controllerby an electric wire routed from the location rearward of the operator'sseat to the console through a side portion of the vehicle body.

In an aspect of a preferred embodiment of the present invention, theworking vehicle may further include a protection structure to protectthe operator's seat. The second manual operator may be attachable to anddetachable from the protection structure.

In an aspect of a preferred embodiment of the present invention, theprotection structure may include pillars extending upward from a leftrear portion and a right rear portion of the vehicle body, respectively,and a beam connecting upper ends of the pillars. The second manualoperator may include a housing attachable to and detachable from any ofthe pillars, and an operable key provided on a surface of the housingother than a mount surface for contact with the pillar.

In an aspect of a preferred embodiment of the present invention, theworking vehicle may further include a falling preventer to prevent thesecond manual operator from falling out of the protection structure.

The above and other elements, features, steps, characteristics andadvantages of the present invention will become more apparent from thefollowing detailed description of the preferred embodiments withreference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of preferred embodiments of the presentinvention and many of the attendant advantages thereof will be readilyobtained as the same becomes better understood by reference to thefollowing detailed description when considered in connection with theaccompanying drawings described below.

FIG. 1 is a control block diagram of a working vehicle.

FIG. 2 illustrates details of a PTO speed change lever.

FIG. 3 is an illustration of automatic steering.

FIG. 4 illustrates how a working vehicle automatically steered behavesduring straight travel.

FIG. 5 illustrates how a working vehicle is automatically steered duringforward travel and during rearward travel.

FIG. 6 illustrates a console located forward of an operator's seat.

FIG. 7 is a perspective view of a working vehicle.

FIG. 8 is a perspective view of a second manual operator and itssurroundings.

FIG. 9 is a flowchart showing how a working vehicle operates.

FIG. 10 illustrates details of a PTO switch.

FIG. 11 illustrates another example of the second manual operator.

FIG. 12 is a side view of a working vehicle.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The preferred embodiments will now be described with reference to theaccompanying drawings, wherein like reference numerals designatecorresponding or identical elements throughout the various drawings. Thedrawings are to be viewed in an orientation in which the referencenumerals are viewed correctly.

The following description discusses preferred embodiments of the presentinvention with reference to the drawings.

The appearance of a working vehicle 1 according to a preferredembodiment is discussed first. FIG. 12 is a side view of the workingvehicle 1. The working vehicle 1 according to the present preferredembodiment is a tractor. Note, however, that working vehicles of thepresent invention are not limited to a tractor as illustrated in FIG. 12, and may be an agricultural machine (agricultural vehicle) such as acombine or a transplanter or a construction machine (constructionvehicle) such as a loader working machine.

In the following description, a forward direction from an operatorseated on an operator's seat 10 of the working vehicle 1 (the directionindicated by arrow A1 in FIG. 12 ) is referred to as a forwarddirection, a rearward direction from the operator (the directionindicated by arrow A2 in FIG. 12 ) is referred to as a rearwarddirection, a leftward direction from the operator is referred to as aleftward direction, and a rightward direction from the operator isreferred to as a rightward direction. Furthermore, a horizontaldirection orthogonal to the front-rear direction of the working vehicle1 is referred to as a vehicle body width direction.

As illustrated in FIG. 12 , the working vehicle 1 includes a vehiclebody 3, a prime mover 4, and a traveling device 7. The vehicle body 3 iscaused by the traveling device 7 to travel forward and rearward. Thetraveling device 7 includes front wheels 7F and rear wheels 7R. Thefront wheels 7F may be tire wheels and may be crawler wheel(s). The rearwheels 7R also may be tire wheels and may be crawler wheel(s). The primemover 4 includes a diesel engine. For another example, the prime mover 4may include an electric motor and/or the like.

The vehicle body 3 is provided with the operator's seat 10 at an upperportion thereof. The vehicle body 3 is provided, at a rear portionthereof, with a linkage portion (not illustrated) including a liftingdevice 8. The linkage portion can have a working implement 2 attachedthereto and detached therefrom. When the working implement 2 isconnected to the linkage portion, the working implement 2 is supportedat the rear of the vehicle body 3, making it possible to allow thevehicle body 3 to tow the working implement 2. The working implement 2is a cultivator for cultivation, a fertilizer spreader to spreadfertilizer, an agricultural chemical spreader to spread agriculturalchemicals, a harvester for harvesting, a mower to mow grass or the like,a tedder to ted grass or the like, a rake to rake grass or the like, abaler to bale grass or the like, and/or the like.

There is a console 9F in front of the operator's seat 10 of the vehiclebody 3. The console 9F is provided with manual operator(s) such as asteering wheel 30, lever(s), and/or switch(es). There is a console 9Llocated leftward of the operator's seat 10, and there is a console 9Rlocated rightward of the operator's seat 10 (see FIG. 7 , discussedlater). The consoles 9L and 9R are each also provided with manualoperator(s) such as lever(s) and/or switch(es).

There is a rollover protection structure (ROPS) 6 located rearward ofthe operator's seat 10 on the vehicle body 3. The ROPS 6 is an exampleof a protection structure to protect the operator seated on theoperator's seat 10 when, for example, the working vehicle 1 rolls over.

The following discusses a configuration of the working vehicle 1. FIG. 1is a control block diagram of the working vehicle 1. The working vehicle1 includes a transmission 5, differentials 20F and 20R, a lifting device8, a steering unit 11, a controller 60, a position detector 40, adisplay 45, actuation valves 25 to 29, and switches 23, 24, and 50 to54.

The transmission 5 is operable to change propelling force for thetraveling device 7 by changing speed stages and to change the directionof travel of the traveling device 7 between forward and rearwarddirections. The transmission 5 includes a propeller shaft (main shaft) 5a, a main transmission portion 5 b, an auxiliary transmission portion 5c, a shuttle portion 5 d, a PTO power transmitting portion 5 e, and afront transmission portion 5 f. The propeller shaft 5 a is rotatablysupported on a housing case (transmission case) of the transmission 5.The propeller shaft 5 a receives power from the crankshaft of the primemover 4. The main transmission portion 5 b includes gears and a shifterto change the connection of the gears. The main transmission portion 5 bis such that when the connection (engagement) of the gears is changedappropriately using the shifter, the main transmission portion 5 bchanges the rotation inputted from the propeller shaft 5 a and outputsit (changes speed stages).

The auxiliary transmission portion 5 c includes gears and a shifter tochange the connection of the gears, similar to the main transmissionportion 5 b. The auxiliary transmission portion 5 c is such that whenthe connection (engagement) of the gears is changed appropriately usingthe shifter, the auxiliary transmission portion 5 c changes the rotationinputted from the main transmission portion 5 b and outputs it (changesspeed stages).

The shuttle portion 5 d includes a shuttle shaft 12 and aforward-and-rearward clutch 13. The shuttle shaft 12 receives power fromthe auxiliary transmission portion 5 c via gear(s) and/or the like. Theforward-and-rearward clutch 13 includes, for example, a hydraulic clutchand/or the like. The forward-and-rearward clutch 13 is connected to afluid passage which is connected to the actuation valve 28. Theactuation valve 28 is supplied with hydraulic fluid delivered by ahydraulic pump 33. The forward-and-rearward clutch 13 is switchedbetween an engaged state and a disengaged state depending on the openingof the actuation valve 28. The actuation valve 28 is, for example, atwo-position switching valve with a solenoid valve. The energization orde-energization of the solenoid of the solenoid valve of the actuationvalve 28 brings the forward-and-rearward clutch 13 into the engagedstate or the disengaged state.

Switching of the forward-and-rearward clutch 13 between the engagedstate and the disengaged state changes the direction of rotation of theshuttle shaft 12. The shuttle shaft 12 is connected to the rear wheeldifferential 20R. The rear wheel differential 20R rotatably supports arear axle 21R having attached thereto the rear wheels 7R.

The PTO (power take-off) power transmitting portion 5 e includes a PTOpropeller shaft 14 and a PTO clutch 15. The PTO propeller shaft 14 isrotatably supported, and can receive power from the propeller shaft 5 a.The PTO propeller shaft 14 is connected to a PTO shaft 16 via gear(s)and/or the like.

The PTO clutch 15 includes, for example, a hydraulic clutch and/or thelike. The PTO clutch 15 is connected to a fluid passage which isconnected to the actuation valve 27. The actuation valve 27 is suppliedwith hydraulic fluid delivered by the hydraulic pump 33. The PTO clutch15 is switched between an engaged state and a disengaged state dependingon the opening of the actuation valve 27. The actuation valve 27 is, forexample, a two-position switching valve with a solenoid valve. Theenergization or de-energization of the solenoid of the solenoid valve ofthe actuation valve 27 brings the PTO clutch 15 into the engaged stateor the disengaged state.

Switching of the PTO clutch 15 between the engaged state and thedisengaged state switches between a state in which power from thepropeller shaft 5 a is transmitted to the PTO propeller shaft 14 and astate in which power from the propeller shaft 5 a is not transmitted tothe PTO propeller shaft 14. The transmission of power from the primemover 4 to the PTO shaft 16 via the propeller shaft 5 a, the PTO clutch15, and the PTO propeller shaft 14 drives and rotates the PTO shaft 16.The PTO shaft 16 is connected to the lifting device 8 and the workingimplement 2. The transmission of driving force from the PTO shaft 16 tothe lifting device 8 and the working implement 2 actuates the liftingdevice 8 and the working implement 2.

The front transmission portion 5 f includes a first clutch 17 and asecond clutch 18. The first clutch 17 and the second clutch 18 canreceive power from the propeller shaft 5 a and, for example, receivepower from the shuttle shaft 12 via gear(s) and transmission shaft(s).The power from the first clutch 17 and the second clutch 18 istransmitted to a front axle 21F via a front transmission shaft 22.Specifically, the front transmission shaft 22 is connected to the frontwheel differential 20F which rotatably supports the front axle 21Fhaving attached thereto the front wheels 7F.

The first clutch 17 and the second clutch 18 each include a hydraulicclutch and/or the like. The first clutch 17 is connected to a fluidpassage which is connected to the actuation valve 25. The actuationvalve 25 is supplied with hydraulic fluid delivered by the hydraulicpump 33. The first clutch 17 switches between its engaged state anddisengaged state depending on the opening of the actuation valve 25. Thesecond clutch 18 is connected to a fluid passage which is connected tothe actuation valve 26. The actuation valve 26 is supplied withhydraulic fluid delivered by the hydraulic pump 33. The second clutch 18switches between its engaged state and the disengaged state depending onthe opening of the actuation valve 26. The actuation valves 25 and 26are each, for example, a two-position switching valve with a solenoidvalve. The energization or the de-energization of the solenoid of thesolenoid valve of each of the actuation valves 25 and 26 switches acorresponding one of the clutches 17 and 18 between the engaged stateand the disengaged state.

In the case where the first clutch 17 is in the disengaged state and thesecond clutch 18 is in the engaged state, power from the shuttle shaft12 is transmitted to the front wheels 7F via the second clutch 18. Thisresults in the state in which the front wheels 7F and the rear wheels 7Rare driven and the rotation speed of the front wheels 7F and therotation speed of the rear wheels 7R are substantially the same (such astate is referred to as a four-wheel-drive-and-equal-speed state, or“4WD equal speed state”). In contrast, in the case where the firstclutch 17 is in the engaged state and the second clutch 18 is in thedisengaged state, this results in the state in which the front wheels 7Fand the rear wheels 7R are driven but the rotation speed of the frontwheels 7F is higher than the rotation speed of the rear wheels 7R (sucha state is referred to as a four-wheel-drive-and-speed-increasing state,or “4WD speed-increasing state”). In the case where both the firstclutch 17 and the second clutch 18 are in the disengaged state, thepower from the shuttle shaft 12 is not transmitted to the front wheels7F. This results in the state in which only the rear wheels 7R aredriven (such a state is referred to as a “two-wheel drive (2WD) state”).

That is, the power from the prime mover 4 is transmitted to the shuttleshaft 12 via the propeller shaft 5 a, the main transmission portion 5 b,the auxiliary transmission portion 5 c, and the forward-and-rearwardclutch 13 to rotate the shuttle shaft 12 in its forward direction orreverse direction to drive the rear wheel differential 20R, thusrotating the rear axle 21R and the rear wheels 7R in the forwarddirection or reverse direction. The power from the prime mover 4 istransmitted from the shuttle shaft 12 to the front transmission shaft 22via the clutch(es) 17 and/or 18 to rotate the front transmission shaft22 in its forward direction or reverse direction to drive the frontwheel differential 20F, thus rotating the front axle 21F and the frontwheels 7F in the forward direction or reverse direction. This causes thevehicle body 3, i.e., the working vehicle 1, to travel forward orrearward.

The lifting device 8 includes one or more lift arms 8 a, one or morelower links 8 b, at least one top link 8 c, one or more lift rods (notillustrated), and one or more lift cylinders 8 e. The front ends of thelift arms 8 a are supported on an upper rear portion of a case(transmission case) housing the transmission 5 such that the lift arms 8a are swingable up and down. The lift arms 8 a are driven by the liftcylinders 8 e to swing (raised or lowered). The lift cylinders 8 e arehydraulic cylinders. The lift cylinders 8 e are connected to thehydraulic pump 33 via the control valve 29. The control valve 29 is, forexample, a solenoid valve and/or the like, and causes the lift cylinders8 e to extend and retract.

The front ends of the lower links 8 b are supported on a lower rearportion of the transmission 5 such that the lower links 8 b areswingable up and down. The front end of the top link 8 c is supported,at a position higher than the lower links 8 b, on a rear portion of thetransmission 5 such that the top link 8 c is swingable up and down. Thelift rods connect the lift arms 8 a and the lower links 8 b. The rearends of the lower links 8 b and the top link 8 c are linked to theworking implement 2. When the lift cylinders 8 e are driven (extend orretract), the lift arms 8 a ascend or descend, and the lower links 8 bconnected to the lift arms 8 a via the lift rods 8 d also ascend ordescend. With this, the working implement 2 swings (is raised orlowered) up or down about the front portions of the lower links 8 b.Note that the working vehicle 1 includes an automatic lifter to raisethe lifting device 8 upon rearward travel of the vehicle body 3. In thepresent preferred embodiment, the automatic lifter includes the liftcylinders 8 e and the control valve 29.

The position detector 40 is operable to detect the position thereof(measured position information including latitude and longitude) using asatellite positioning system (positioning satellite(s)) such as D-GPS,GPS, GLONASS, BeiDou, Galileo, and/or Michibiki. Specifically, theposition detector 40 receives satellite signal(s) (position(s) ofpositioning satellite(s), time of transmission, correction information,and/or the like) sent from positioning satellite(s) and detects theposition (for example, latitude and longitude) based on the satellitesignal(s). The position detector 40 includes a receiver 41 and aninertial measurement unit (IMU) 42. The receiver 41 includes an antennaand/or the like and receives satellite signal(s) from positioningsatellite(s). The receiver 41 is attached to, for example, the ROPS 6(FIG. 12 ).

The inertial measurement unit 42 includes an acceleration sensor todetect acceleration, a gyroscope sensor to detect angular velocity,and/or the like. It is possible to detect the roll angle, pitch angle,yaw angle, and/or the like of the vehicle body 3 based on the result ofdetection by the inertial measurement unit 42.

The steering unit 11 enables manual steering in which the operatorseated on the operator's seat 10 operates the steering wheel 30 to steerthe vehicle body 3, and automatic steering in which the vehicle body 3is steered automatically without the operator's operation.

The steering unit 11 includes the steering wheel 30, a steering shaft(rotary shaft) 31 rotatably supporting the steering wheel 30, and anassist mechanism (power steering system) 32. The assist mechanism 32assists the steering shaft 31 and the steering wheel 30 in rotatingusing hydraulic pressure and/or the like. The assist mechanism 32includes a control valve 34 which is supplied with hydraulic fluiddelivered by the hydraulic pump 33, and a steering cylinder 35 actuatedby the control valve 34. The control valve 34 is, for example, athree-way switching valve which achieves multi-position switching bymovement of a spool or the like, and is switched in position accordingto the steering direction (direction of rotation) of the steering shaft31. The steering cylinder 35 is connected to arms (knuckle arms) 36 tochange the orientation of the front wheels 7F.

Upon operation (rotation) by the operator of the steering wheel 30 in afirst direction or a second direction, the position and opening of thecontrol valve 34 are changed according to the direction of rotation ofthe steering wheel 30, and the steering cylinder 35 extends or retractsleftward or rightward according to the position and opening of thecontrol valve 34, thus making it possible to change the steeringdirection of the front wheels 7F. That is, the direction of travel ofthe vehicle body 3 can be changed leftward or rightward by manualsteering using the steering wheel 30.

The steering unit 11 includes an automatic steering mechanism 37. Theautomatic steering mechanism 37 performs automatic steering of thevehicle body 3, and automatically steers the vehicle body 3 based on theposition of the vehicle body 3 detected by the position detector 40. Theautomatic steering mechanism 37 includes a steering motor 38 and a gearmechanism 39. The steering motor 38 can be controlled in terms of thedirection of rotation, speed of rotation, angle of rotation, and/or thelike based on the vehicle body position. The gear mechanism 39 includesgear(s) provided on and rotate together with the steering shaft 31, andgear(s) provided on and rotate together with the rotary shaft of thesteering motor 38.

The rotation of the rotary shaft of the steering motor 38 in its forwarddirection causes the steering shaft 31 to automatically rotate (turn) inits forward direction via the gear mechanism 39, thus making it possibleto steer the front wheels 7F in one of the left and right directions.The rotation of the rotary shaft of the steering motor 38 in the reversedirection causes the steering shaft 31 to automatically rotate in thereverse direction via the gear mechanism 39, thus making it possible tosteer the front wheels 7F in the other of the left and right directions.

The controller 60 includes a central processing unit (CPU), one or morememories, and/or the like. The controller 60 controls the operation ofeach element of the working vehicle 1. The display 45 is provided on theconsole 9F (FIG. 12 ) in front of the operator's seat 10. The display 45displays operation information of the working vehicle 1, various otherinformation relating to the working vehicle 1, and/or the like. Thedisplay 45 also functions as a notifier to provide notificationsrelating to the automatic steering of the vehicle body 3.

The switches 50 to 54 are switches (operation actuators) for automaticsteering operated by the operator of the working vehicle 1. Of these,the mode switch 50 is used to issue an instruction to enter a settingsmode in which settings regarding automatic steering are made. Thesettings mode is a mode in which various settings regarding automaticsteering are made before the automatic steering is started. For example,start and end points of a reference travel line (described later) andthe like can be set in the settings mode.

The defining switch 51 is used to issue an instruction to define areference travel line based on which automatic steering is to beperformed, when the settings mode is enabled. The steering switches 52and 54 are used to issue an instruction to start or stop the automaticsteering of the vehicle body 3 based on the reference travel line. Thecorrection switch 53 is used to issue an instruction to correct theposition of the vehicle body 3 detected by the position detector 40.Specifically, the position of the vehicle body 3 calculated based onsatellite signal(s) (position(s) of positioning satellite(s), time oftransmission, correction information, and/or the like) and measuredinformation (acceleration, angular velocity) measured by the inertialmeasurement unit 42 can be corrected by operating the correction switch53. The controller 60 detects the operation of the switches 50 to 54.

The PTO speed change lever 24 is an operation actuator for the PTO to beoperated by the operator of the working vehicle 1. FIG. 2 illustratesdetails of the PTO speed change lever 24. The PTO speed change lever 24is operated to change the direction of rotation of the PTO shaft 16 andto change the rotation speed of the PTO shaft 16 (change speed stages).The PTO speed change lever 24 is provided on the console 9L leftward ofthe operator's seat 10 such that the PTO speed change lever 24 isswingable forward and rearward (see FIGS. 12 and 7 ). The PTO speedchange lever 24 is swung, and thus is switched from a neutral positionQn as illustrated in FIG. 2 to one of the following driving positions: afirst forward rotation position Q1; a second forward rotation positionQ2; a third forward rotation position Q3; or a reverse rotation positionQb.

While the PTO speed change lever 24 is not operated, the lever 24 is inthe neutral position Qn in which a movable terminal 24 f moving with thelever 24 is connected to a fixed terminal 24 a to allow a signal to beinputted into an input port 60 a of the controller 60 from a powersource via the terminals 24 f and 24 a and an input line 62 a. Withthis, the controller 60 detects that the PTO speed change lever 24 is inthe neutral position Qn. The PTO shaft 16 here is in its stopped state.

Once the PTO speed change lever 24 has been swung in the forwarddirection A1 by one level and thus the position of the lever 24 has beenchanged to the first forward rotation position Q1, the movable terminal24 f is connected to a fixed terminal 24 b to allow a signal to beinputted into an input port 60 b of the controller 60 from the powersource via the terminals 24 f and 24 b and an input line 62 b. Once thePTO speed change lever 24 has been swung in the forward direction A1 bytwo levels and thus the position of the lever 24 has been changed to thesecond forward rotation position Q2, the movable terminal 24 f isconnected to a fixed terminal 24 c to allow a signal to be inputted intoan input port 60 c of the controller 60 from the power source via theterminals 24 f and 24 c and an input line 62 c. Once the PTO speedchange lever 24 has been swung in the forward direction A1 by threelevels and thus the position of the lever 24 has been changed to thethird forward rotation position Q3, the movable terminal 24 f isconnected to a fixed terminal 24 d to allow a signal to be inputted intoan input port 60 d of the controller 60 from the power source via theterminals 24 f and 24 d and an input line 62 d.

Upon receipt of the signal at the input port 60 b, 60 c, or 60 dthereof, the controller 60 detects that the PTO speed change lever 24has been moved to the first forward rotation position Q1, the secondforward rotation position Q2, or the third forward rotation position Q3.Once the PTO speed change lever 24 has been moved to the first forwardrotation position Q1, the PTO shaft 16 is driven to rotate in theforward direction at a predetermined first rotation speed by theoperation of the transmission 5. Once the PTO speed change lever 24 hasbeen moved to the second forward rotation position Q2, the PTO shaft 16is driven to rotate in the forward direction at a predetermined secondrotation speed higher than the first rotation speed by the operation ofthe transmission 5. Once the PTO speed change lever 24 has been moved tothe third forward rotation position Q3, the PTO shaft 16 is driven torotate in the forward direction at a predetermined third rotation speedhigher than the second rotation speed by the operation of thetransmission 5.

Once the PTO speed change lever 24L has been swung in the rearwarddirection A2 and thus the position of the lever 24 has been changed tothe reverse rotation position Qb, the movable terminal 24 f is connectedto a fixed terminal 24 e to allow a signal to be inputted into an inputport 60 e of the controller 60 from the power source via the terminals24 f and 24 e and an input line 62 e. With this, the controller 60detects that the PTO speed change lever 24 is in the reverse rotationposition Qb. The PTO shaft 16 here is driven to rotate in the reversedirection at a predetermined rotation speed by the operation of thetransmission 5.

The following discusses automatic steering of the working vehicle 1.FIG. 3 is an illustration of the automatic steering of the workingvehicle 1. Before the automatic steering is performed, a referencetravel line L1 based on which the automatic steering is to be performedis defined first. After the reference travel line L1 is defined, plannedtravel line(s) L2 parallel to the reference travel line L1 is/aredefined, thus making it possible to perform the automatic steering. Inthe automatic steering, the direction of travel of the vehicle body 3 ofthe working vehicle 1 is automatically controlled such that the positionof the vehicle body 3 measured by the position detector 40 matches theplanned travel line(s) L2.

Specifically, before the automatic steering is performed, the operatoroperates the working vehicle 1 to move the working vehicle 1 to apredetermined position in an agricultural field (S1), and operates themode switch 50 at the predetermined position. This brings the controller60 into the settings mode. Next, once the operator has operated thedefining switch 51 to register a start point (S2), the controller 60sets the position of the vehicle body 3 measured at this time by theposition detector 40 as a start point P10 of the reference travel lineL1 (S3).

Next, the operator manually steers the working vehicle 1 to travel fromthe start point P10 of the reference travel line L1 (S4), and brings theworking vehicle 1 to stop at a desired position. Then, once the operatorhas operated the defining switch 51 to register an end point (S5), thecontroller 60 sets the position of the vehicle body 3 measured at thistime by the position detector 40 as an end point P11 of the referencetravel line L1 (S6). With this, a straight line connecting the startpoint P10 and the end point P11 is defined as the reference travel lineL1.

Next, the operator moves the working vehicle 1 to a different area fromthe area in which the reference travel line L1 has been defined (S7),and operates the steering switch 52 (or the steering switch 54 (FIG. 1)) to make a start (S8). This causes the controller 60 to define aplanned travel line L2 which is a straight line parallel to thereference travel line L1 (S9). Then, the controller 60 actuates theautomatic steering mechanism 37 to start the automatic steering and theoperator operates travel operation actuator(s) (such as an acceleratorpedal 182 and/or a brake pedal 183 in FIG. 1 , a shuttle lever 181 inFIG. 6 , and/or the like) provided on the vehicle body 3, causing theworking vehicle 1 to travel along the planned travel line L2. Thereference travel line L1 and the planned travel line L2 are displayed bythe display 45 and visually recognizable to the operator.

For example, if the position of the vehicle body 3 is located leftwardof the planned travel line L2, the controller 60 actuates the automaticsteering mechanism 37 to steer the front wheels 7F right. If theposition of the vehicle body 3 is located rightward of the plannedtravel line L2, the controller 60 actuates the automatic steeringmechanism 37 to steer the front wheels 7F left. During the automaticsteering, the operator can change the travel speed (vehicle speed) ofthe working vehicle 1 by, for example, changing the degree of operationof the accelerator pedal 182 and/or the like and/or by changing thespeed stage of the transmission 5.

After the start of the automatic steering, once the operator hasoperated the steering switch 52 to make a stop at a desired position,the controller 60 stops (ends) the automatic steering. Specifically, theend point of the planned travel line L2 is set upon stoppage of theautomatic steering caused by the operation of the steering switch 52 tomake a stop. That is, the length of the planned travel line L2 from thestart point to the end point can be set, for example, to be longer thanor shorter than the reference travel line L1. In other words, theplanned travel line L2 is not associated with the length of thereference travel line L1, and the planned travel line L2 makes itpossible to cause the working vehicle 1 to be automatically steered totravel a longer distance than the reference travel line L1.

There are cases in which, while the working vehicle 1 is automaticallysteered to travel, the position of the vehicle body 3 detected by theposition detector 40 deviates from the actual position of the vehiclebody 3. Such a deviation of the position of the vehicle body 3 can becorrected by the operator operating the correction switch 53.

The following discusses the relationship between the operation of thecorrection switch 53 and the behavior of the working vehicle 1 (pathtraveled by the working vehicle 1) during the automatic steering. FIG. 4illustrates an example of the behavior of the working vehicle 1 whilethe working vehicle 1 is automatically steered to travel straight. InFIG. 4 , for example, for a certain period of time from the start of theautomatic steering of the working vehicle 1, the actual position W2 ofthe vehicle body 3 (actual position) matches the position W1 of thevehicle body 3 detected by the position detector 40 (calculated vehiclebody position), and the actual position W2 matches the planned travelline L2. In such a case, the working vehicle 1 travels along the plannedtravel line L2. That is, the working vehicle 1 travels along the plannedtravel line L2 in a section P1 in which there are no errors inpositioning performed by the position detector 40 and the calculatedvehicle body position W1 matches the actual position W2.

Note that, if there are no errors in positioning by the positiondetector 40 and no corrections have been made, the calculated vehiclebody position W1 and the vehicle body position W3 corrected by thecorrection switch 53 (corrected vehicle body position) have the samevalue. The corrected vehicle body position W3 is determined bysubtracting, from the calculated vehicle body position W1, a correctionamount inputted via the correction switch 53 (corrected vehicle bodyposition W3=calculated vehicle body position W1−correction amount).

For example, assume that, at or near a position P20 in FIG. 4 , an erroroccurs in positioning by the position detector 40 and the calculatedvehicle body position W1 detected by the position detector 40 deviatesrightward from the planned travel line L2 (actual position W2) due tovarious influences although the actual position W2 does not deviate fromthe planned travel line L2, and the deviation W4 is maintained. In sucha case, the controller 60 determines that there is a deviation betweenthe calculated vehicle body position W1 and the planned travel line L2,and steers the vehicle body 3 left to eliminate the deviation W4 of thecalculated vehicle body position W1 from the planned travel line L2.This causes the actual position W2 of the vehicle body 3 to shiftleftward away from the planned travel line L2.

After that, the operator notices that the position of the vehicle body 3deviates leftward from the planned travel line L2, and operates thecorrection switch 53 at a position P21 to input a correction amount bywhich the calculated vehicle body position W1 is caused to approach theactual position W2. With this, the correction amount is added to thecalculated vehicle body position W1, and the corrected vehicle bodyposition W3 matches the actual position W2. That is, it is possible tocorrect the position of the vehicle body 3 detected by the positiondetector 40 in a direction that eliminates the deviation W4 occurred ator near the position P20, by inputting the correction amount using thecorrection switch 53.

Note that, if the actual position W2 deviates leftward from the plannedtravel line L2 at a point in time after the correction of the positionof the vehicle body 3 (at the position P21) as illustrated in FIG. 4 ,the vehicle body 3 is steered right by automatic steering to cause theactual position W2 of the vehicle body 3 to move along the plannedtravel line L2.

It is noted that, although FIG. 3 discussed above provides a case inwhich automatic steering of the working vehicle 1 is performed duringforward travel of the working vehicle 1, the automatic steering of theworking vehicle 1 can also be performed during rearward travel of theworking vehicle 1.

FIG. 5 illustrates how automatic steering is performed during forwardtravel and rearward travel of the working vehicle 1. For example, whenautomatic steering is performed in an agricultural field H1, thecontroller 60 defines a straight portion SLn (n=1, 2, 3 . . . ) of aplanned travel line L2 parallel to the reference travel line L1 eachtime the steering switch 52 or 54 is operated to make a start, thusobtaining a plurality of straight portions SLn of a plurality of theplanned travel lines L2. For example, when the steering switch 52 isoperated to make a start at a start position ST1 to issue an instructionto start automatic steering, a first straight portion SL1 is defined.Then, the controller 60 controls the transmission 5 and the automaticsteering mechanism 37 to perform automatic steering while causing thevehicle body 3 to travel along the straight portion SL1. When thesteering switch 52 is operated to make a stop at an end position EN1 toissue an instruction to stop the automatic steering, the controller 60controls the automatic steering mechanism 37 to end (stop) the automaticsteering of the vehicle body 3 during forward travel along the straightportion SL1.

Then, for example, assume that, in order to do work with a workingimplement 2 attached to the working vehicle 1, after the automaticsteering during forward travel along the first straight portion SL1, theoperator is about to cause automatic steering to be performed duringrearward travel of the vehicle body 3 without turning the workingvehicle 1.

In such a case, for example, when the steering switch 54 is operated tomake a start at a start position ST2 to issue an instruction to startautomatic steering, the controller 60 defines a second straight portionSL2. Then, the controller 60 controls the transmission 5 and theautomatic steering mechanism 37 to perform automatic steering whilecausing the vehicle body 3 to travel rearward along the straight portionSL2. Specifically, when the steering switch 54 is operated to startautomatic steering, the controller 60 controls driving of the steeringmotor 38 of the automatic steering mechanism 37 and rotates the steeringshaft 31 to steer the front wheels 7F so that the vehicle body 3 travelsrearward along the straight portion SL2. Then, when the steering switch54 is operated to make a stop at an end position EN2 to issue aninstruction to stop the automatic steering, the controller 60 controlsthe automatic steering mechanism 37 to end the automatic steering of thevehicle body 3 during rearward travel along the straight portion SL2.

The following discusses the console 9F. FIG. 6 illustrates the console9F in front of the operator's seat 10 as seen from the operator's seat10. The console 9F is provided with the steering wheel 30 and thesteering shaft 31 connected to the steering wheel 30. The steering shaft31 has its outer periphery covered by a steering post 180. The steeringpost 180 has its outer periphery covered by a cover 177. The cover 177includes a panel cover 178 and a column cover 179.

The panel cover 178 supports the display 45. The panel cover 178includes an upper plate portion 178 a provided with a support portion178 e to support the display 45. The support portion 178 e supports thedisplay 45 at a position in front of the steering shaft 31 and below thesteering wheel 30. The upper plate portion 178 a includes a mountsurface 178 f which is located at a position rearward of the supportportion 178 e and below the steering wheel 30. The support portion 178 eand the mount surface 178 f are continuous with each other. The supportportion 178 e is located at a front portion of the upper plate portion178 a, and the mount surface 178 f is located at a rear portion of theupper plate portion 178 a. The mount surface 178 f has thereon the modeswitch 50 and the correction switch 53. The mode switch 50 and thecorrection switch 53 are located in the vicinity of the steering shaft31.

The panel cover 178 includes a left plate portion 178 b through whichthe shuttle lever 181 projects. The shuttle lever 181 is operated tochange the direction of travel of the vehicle body 3 to the forwarddirection A1 or the rearward direction A2. Specifically, the operation(swinging) of the shuttle lever 181 in the forward direction A1 (upwarddirection in FIG. 6 ) causes the forward-and-rearward clutch 13 tooutput forward-traveling power to the traveling device 7, thus changingthe direction of travel of the vehicle body 3 to the forward directionA1. The operation of the shuttle lever 181 in the rearward direction A2(downward direction in FIG. 6 ) causes the forward-and-rearward clutch13 to output rearward-traveling power to the traveling device 7, thuschanging the direction of travel of the vehicle body 3 to the rearwarddirection A2. While the shuttle lever 181 is in the neutral position,power is not outputted to the traveling device 7.

The column cover 179 is located below the steering wheel 30 and coversan upper portion of the steering shaft 31. The column cover 179 issubstantially in the form of a rectangular tube, and projects upwardfrom the mount surface 178 f of the panel cover 178. That is, the mountsurface 178 f is located around the column cover 179. Therefore, themode switch 50 and the correction switch 53 attached to the mountsurface 178 f are located in the vicinity of the column cover 179.

The mode switch 50 is located diagonally leftward and downward of thesteering shaft 31. The mode switch 50 is a push switch. The mode switch50 is electrically connected to the controller 60 by an electric wire 70(FIG. 1 ) routed inside the console 9F.

The correction switch 53 is located diagonally rightward and downward ofthe steering shaft 31. The correction switch 53 is electricallyconnected to the controller 60 by an electric wire 73 (FIG. 1 ) routedinside the console 9F. The correction switch 53 includes a leftcorrection key 53L and a right correction key 53R which are push keys.The pressing of the left correction key 53L causes a left correctionamount, by which the position of the vehicle body 3 is correctedleftward, to be inputted into the controller 60. The pressing of theright correction key 53R causes a right correction amount, by which theposition of the vehicle body 3 is corrected rightward, to be inputtedinto the controller 60.

The left correction amount and the right correction amount can each beincreased by increasing the number of times a corresponding correctionkey 53L or 53R is pressed. Each correction amount is determined bymultiplying the number of times the corresponding correction key 53L or53R is pressed by a predetermined unit amount (correction amount=numberof times key is pressed x unit amount). That is, the correction amountincreases by a unit amount (for example, several centimeters or severaltens of centimeters) each time the corresponding correction key 53L or53R is pressed. The controller 60 detects the number of times thecorrection switch 53 is pressed, and calculates the correction amountbased on the number.

There is an automatic steering lever 56 located leftward of the steeringshaft 31 such that the automatic steering lever 56 projects leftward.The automatic steering lever 56 is swingable upward, downward, forwardand rearward from a neutral position about its proximal portion locatednear the steering shaft 31. The proximal portion of the automaticsteering lever 56 is located inside the column cover 179. The columncover 179 has located therein the foregoing defining switch 51 and thesteering switch 52 (FIG. 1 ) (details are not illustrated). The definingswitch 51 and the steering switch 52 are electrically connected to thecontroller 60 by electric wires 71 and 72 (FIG. 1 ) routed inside theconsole 9F, respectively.

When the settings mode has been enabled by operation of the mode switch50, the swinging of the automatic steering lever 56 from the neutralposition in the rearward direction causes the defining switch 51 to beoperated to register a start point, and an instruction (signal) to setthe position of the vehicle body 3 detected at this time by the positiondetector 40 as the start point P10 of the reference travel line L1 isinputted into the controller 60. The swinging of the automatic steeringlever 56 from the neutral position in the forward direction causes thedefining switch 51 to be operated to register an end point, and aninstruction to set the position of the vehicle body 3 detected at thistime by the position detector 40 as the end point P11 of the referencetravel line L1 is inputted into the controller 60.

After that, the swinging of the automatic steering lever 56 from theneutral position in the downward direction causes the steering switch 52to be operated to make a start, and an instruction to start automaticsteering is inputted into the controller 60. Furthermore, the swingingof the automatic steering lever 56 from the neutral position in theupward direction causes the steering switch 52 to be operated to make astop, and an instruction to stop the automatic steering is inputted intothe controller 60.

The mode switch 50, the correction switch 53, and the automatic steeringlever 56 are located in a concentrated manner in the vicinity of thesteering shaft 31. This makes it possible for the operator to know thepositions of the switches 50 and 53 and the lever 56 at a glance. Theoperator can also operate the switches 50 and 53 and the lever 56 whileremaining seated on the operator's seat 10 without having to changepositions. It follows that, when automatic steering is performed duringforward travel of the vehicle body 3, the switches 50, 51, 52, and 53for automatic steering are easily operable and that accidental operationof the switches 50, 51, 52, and 53 can be prevented. The switches 50 to53 are a first manual operator located in or on the console 9F in frontof the operator's seat 10.

Note that the arrangement of the switches 50 to 53 and the lever 56 isnot limited to the foregoing arrangement, and may be any arrangement.The defining switch 51 and the steering switch 52 may be configured suchthat they can be operated using respective individual control knobs suchas lever(s), button(s), and/or the like.

FIG. 7 is a front perspective view of the working vehicle 1. The console9L located leftward of the operator's seat 10 is provided with theforegoing PTO speed change lever 24 to operate the PTO shaft 16. TheROPS 6 is located rearward of the operator's seat 10 (downstream of theoperator's seat 10 in the rearward direction A2). The ROPS 6 includes apair of left and right pillars 6L and 6R and a beam 6 b. The pillars 6Land 6R and the beam 6 b are made of steel. The pillar 6L extends upwardfrom a left rear portion of the vehicle body 3, and the pillar 6Rextends upward from a right rear portion of the vehicle body 3. The beam6 b connects upper ends of the pillars 6L and 6R.

The left pillar 6L has a switch box 19 attached to its front surface.The switch box 19 has a magnet (not illustrated) fixed to its mountsurface 19 b (back surface of the switch box 19 facing in the rearwarddirection A2 in FIG. 7 , illustrated in FIG. 8 discussed later) whichcontacts the pillar 6L. The switch box 19 is attachable to anddetachable from the pillar 6L using the magnetic force of the magnet.

There is the steering switch 54 located on a front surface 19 f facingin the forward direction A1 that is one of the surfaces of the switchbox 19 other than the mount surface 19 b. The steering switch 54 is asecond manual operator for automatic steering attachable and detachableat a location rearward of the operator's seat 10, and has the samefunctions as the steering switch 52 included in the first manualoperator located in/on the console 9F.

The steering switch 54 includes an ON key 54 a and an OFF key 54 b. Theswitch box 19 includes therein contact(s) of the steering switch 54,electric wire(s), and/or the like. The switch box 19 is a housing of thesecond manual operator. The steering switch 54 is electrically connectedto the controller 60 by an electric wire 74 (see also FIG. 1 ) routedfrom the switch box 19 located rearward of the operator's seat 10 to theconsole 9F through the interior of a left portion of the vehicle body 3.

Pressing of the ON key 54 a causes the steering switch 54 to be operatedto make a start, and an instruction to start automatic steering isinputted into the controller 60. Pressing of the OFF key 54 b causes thesteering switch 54 to be operated to make a stop, and an instruction tostop the automatic steering is inputted into the controller 60.

When automatic steering is performed during rearward travel of theworking vehicle 1, the operator seated on the operator's seat 10 looksback (looks in the rearward direction A2) to ensure safety behind theworking vehicle 1 (area downstream of the working vehicle 1 in therearward direction A2). The operator looking back can visually recognizethe ON key 54 a and the OFF key 54 b. Therefore, the operator pressesthe ON key 54 a to start automatic steering during rearward travel, andpresses the OFF key 54 b to stop the automatic steering during therearward travel. That is, the steering switch 54 is a manual operatorfor automatic steering for rearward travel that is to be operated tostart and stop automatic steering during rearward travel of the vehiclebody 3.

Note, however, that the steering switches 52 and 54 can be used(enabled) during forward travel of the vehicle body 3 and rearwardtravel of the vehicle body 3. That is, during forward travel of thevehicle body 3 and during rearward travel of the vehicle body 3, theoperation of one of the steering switches 52 and 54 to make a start ormake a stop causes the controller 60 to start or stop automaticsteering. Note, however, that, once the controller 60 has startedautomatic steering in response to the operation of one of the steeringswitches 52 and 54 to make a start, the controller 60 disables the otherof the steering switches 52 and 54 until stopping (ending) the automaticsteering in response to the operation of the one of the steeringswitches 52 and 54 to make a stop.

Specifically, for example, once the controller 60 has started automaticsteering during rearward travel in response to the operation of thesteering switch 54 (which is located downward in the rearward directionA2) to make a start, the controller 60 disables the steering switch 52,i.e., does not accept the operation of the steering switch 52, untilstopping the automatic steering in response to the operation of thesteering switch 54 to make a stop. For example, once the controller 60has started automatic steering during forward travel in response to theoperation of the steering switch 52 (which is located downward in theforward direction A1) to make a start, the controller 60 disables thesteering switch 54, i.e., does not accept the operation of the steeringswitch 54, until stopping the automatic steering in response to theoperation of the steering switch 52 to make a stop.

FIG. 8 is a rear perspective view of the switch box 19 and the pillar6L. The switch box 19 provided with the steering switch 54 is preventedfrom falling out of the pillar 6L with a falling preventer 57. Thefalling preventer 57 includes a wire 58 and a snap ring 59. The wire 58passes sideways through an upper portion of the switch box 19 andsurrounds the pillar 6L. The opposite ends of the wire 58 locatedrearward of the pillar 6L have through holes 58 a and 58 b,respectively. The snap ring 59 is located rearward of the pillar 6L andpasses through the through holes 58 a and 58 b of the wire 58. Thus, thewire 58 and the snap ring 59 restrict the switch box 19 from separatingfrom the vicinity of the pillar 6L.

In FIGS. 7 and 8 , the switch box 19 with the steering switch 54 isattached to the front surface of the left pillar 6L of the ROPS 6. Note,however, that the switch box 19 can also be attached to the right pillar6R. Since the electric wire 74 for the switch box 19 is drawn out(upward) of the vehicle body 3 at a location rearward of the operator'sseat 10 as illustrated in FIG. 7 , the electric wire 74 does not hinderthe operation or work. Furthermore, since the electric wire 74 from therear of the operator's seat 10 is long enough to be attached to thepillar 6L or 6R, it is easy to detach the switch box 19 from one of thepillars 6L and 6R and attach it to the other and vice versa. The switchbox 19 can also be attached to any surface of the pillar 6L or 6R, canbe attached to any surface of the beam 6 b, and can be attached to anyposition on the vehicle body 3. Note that, in consideration of the easeof operation of the steering switch 54, it is not recommended that theswitch box 19 be attached to the beam 6 b (FIG. 7 ) located higher thanthe operator seated on the operator's seat 10.

The following discusses control of automatic steering linked to the PTOshaft 16 of the working vehicle 1. FIG. 9 is a flowchart showing theoperation of the working vehicle 1. The steps in FIG. 9 are performed bythe controller 60 in accordance with prestored software program(s).

First, the controller 60 detects the state of the PTO speed change lever24 and the PTO shaft 16 (T1). The state of the PTO shaft 16 is detectedbased on, for example, the opening of the actuation valve 27.Alternatively, a sensor to detect the rotating state of the PTO shaft 16may be provided and the controller 60 may detect the state of the PTOshaft 16 based on a signal from the sensor.

If the PTO speed change lever 24 is in the neutral position Qn and thePTO shaft 16 is in the stopped state (YES in T2), the controller 60allows automatic steering for rearward travel (T3). Note that automaticsteering for forward travel is always allowed. Next, after the modeswitch 50 and/or the defining switch 51 is/are operated to define areference travel line L1, once the steering switch 52 or 54 has beenoperated to make a start (YES in T4), the controller 60 controls theautomatic steering mechanism 37 to start automatic steering (T5). Withthis, automatic steering during forward travel or automatic steeringduring rearward travel of the working vehicle 1 is performed dependingon the direction of travel of the vehicle body 3.

The controller 60 notifies the operator of the working vehicle 1 ofautomatic steering information indicative of the state of the automaticsteering being performed, guidance relating to the automatic steering,and/or the like by causing the display 45 to display the automaticsteering information (T6). It is noted here that the display 45 may becaused to display, for example, a reference travel line L1 and/orplanned travel line(s) L2 for the working vehicle 1 in the agriculturalfield H1, the position of the working vehicle 1, and/or the like asillustrated in FIG. 5 . Alternatively, an audio or visual notificationof the state of the automatic steering and guidance relating to theautomatic steering may be provided using a beeper (buzzer), a speaker,lighting, and/or the like of the working vehicle 1.

The controller 60 disables the steering switch that has not beenoperated to make a start (T7). With this, for example, even if thesteering switch that has not been operated to make a start is operatedaccidentally, the automatic steering is not stopped or restarted inresponse to the operation.

After that, when the same steering switch as the switch whose operationto make a state was detected in step T4 is operated to make a stop (YESin T8), the controller 60 controls the automatic steering mechanism 37to stop the automatic steering (T9). The controller 60 also stops thenotification of the automatic steering information performed by thedisplay 45 (T10), and stops disabling the steering switch that has notbeen operated (T11).

In contrast, if the PTO speed change lever 24 is not in the neutralposition Qn or the PTO shaft 16 is in its driven state (NO in T2), thecontroller 60 prohibits the automatic steering for rearward travel(T12). It is noted here that the automatic steering for forward travelis not prohibited.

Next, once the steering switch 52 or 54 has been operated to make astart (YES in T13), the controller 60 detects the direction of travel ofthe vehicle body 3 based on the operating state of the shuttle lever 181(FIG. 6 ), the rotating state of the wheels 7F and/or 7R, and/or thelike. Note that sensor(s) to detect the operating state of the shuttlelever 181, the rotating state of the wheels 7F and/or 7R, and/or thelike may be provided. If the direction of travel of the vehicle body 3is the forward direction A1 (NO in T14), the controller 60 controls theautomatic steering mechanism 37 to start the automatic steering duringforward travel (T5). The controller 60 then performs step T6 and thesubsequent steps.

If the direction of travel of the vehicle body 3 is the rearwarddirection A2 (YES in T14), the controller 60 does not start theautomatic steering during rearward travel and provides, to the operator,a notification including, for example, a message indicating that theautomatic steering during rearward travel is prohibited, by causing thedisplay 45 to display the message (T15). The controller 60 alsoprovides, to the operator, a notification including guidance to promptthe operator to move the PTO speed change lever 24 to the neutralposition Qn, by causing the display 45 to display the guidance (T16).

The notifications provided via the display 45 in steps T15 and T16 maybe continued until the PTO speed change lever 24 is moved to the neutralposition Qn and the PTO shaft 16 is brought into the stopped state, ormay be performed for a certain period of time, for example.Alternatively or additionally, an audio or visual notification includingan indication that the automatic steering during rearward travel isprohibited, the guidance to prompt the operator to move the PTO speedchange lever 24 to the neutral position Qn, and/or the like may beprovided in steps T15 and T16 using a beeper (buzzer), a speaker,lighting, and/or the like of the working vehicle 1. That is, a notifierto provide a visual, audio, and/or tactile notification other than thedisplay 45 may be used. Furthermore, for example, a notificationincluding guidance to prompt the operator to stop the PTO shaft 16 maybe provided instead of step T16.

In the foregoing preferred embodiment, the controller 60 prohibits theautomatic steering during rearward travel if the PTO speed change lever24 is not in the neutral position Qn or if the PTO shaft 16 is in thedriven state (NO in T2 in FIG. 9 ). Note, however, that the controller60 may prohibit the automatic steering during rearward travel based onwhether or not either one of those conditions regarding the PTO speedchange lever 24 and the PTO shaft 16 is satisfied.

In the foregoing preferred embodiment, if the steering switch 52 or 54is operated to issue an instruction to start automatic steering and thevehicle body 3 travels rearward (YES in step T13 in FIG. 9 , YES in stepT14 in FIG. 9 ), the display 45 is caused to provide a notificationindicating that the automatic steering during rearward travel isprohibited and a notification including guidance for moving the PTOspeed change lever 24 (steps T15 and T16). However, also if the steeringswitch 52 or 54 is operated to issue an instruction to start automaticsteering and the vehicle body 3 travels forward (YES in step T13, NO instep T14), the display 45 may be caused to provide a notificationindicating that the automatic steering during rearward travel isprohibited and a notification including guidance for moving the PTOspeed change lever 24. Note that, in such a case, it is preferable thatthe display 45 and/or the like be caused to provide a notificationincluding guidance to prompt the operator to move the PTO speed changelever 24 to the neutral position Qn when the automatic steering isperformed during rearward travel.

In the foregoing preferred embodiment, the PTO speed change lever 24 isprovided as an operation actuator to control driving of the PTO shaft16. Note, however, that, for example, the PTO switch 23 as illustratedin FIG. 10 may be provided in addition to the lever 24 to improve safetyand/or the like.

FIG. 10 illustrates details the PTO switch 23. The PTO switch 23 isoperated to issue an instruction to drive or stop the PTO shaft 16. ThePTO switch 23 is, for example, provided on the console 9L locatedleftward of the operator's seat 10 such that the PTO switch 23 isoperable. The PTO switch 23 is movable from its neutral position Qx toits OFF position Qy or ON position (driving position) Qz.

When the PTO switch 23 has not been operated, the PTO switch 23 is inthe neutral position Qx in which a movable terminal 23 d of the switch23 is connected to a fixed terminal 23 a to allow a signal to beinputted into an input port 60 g of the controller 60 from the switch 23via an input line 61 a. With this, the controller 60 detects that thePTO switch 23 is in the neutral position Qx. The PTO shaft 16 is in itsstopped state, and even if, for example, the PTO speed change lever 24(FIG. 2 ) is moved to the driving position Q1, Q2, Q3, or Qb, the PTOshaft 16 is not driven to rotate.

Once the PTO switch 23 has been operated to move to the ON position Qz,the movable terminal 23 g is connected to a fixed terminal 23 c to allowa signal to be inputted into an input port 60 i of the controller 60from the switch 23 via an input line 61 c. With this, the controller 60detects that the PTO switch 23 has been moved to the ON position Qz. ThePTO shaft 16 here can be driven by the operation of the transmission 5.That is, the movement of the PTO speed change lever 24 to the drivingposition Q1, Q2, Q3, or Qb causes the PTO shaft 16 to be driven torotate at a predetermined rotation speed in the forward direction orreverse direction.

Once the PTO switch 23 has been operated to move to the OFF position Qy,the movable terminal 23 g is connected to a fixed terminal 23 b to allowa signal to be inputted into an input port 60 h of the controller 60from the switch 23 via an input line 61 b. With this, the controller 60detects that the PTO switch 23 has been moved to the OFF position Qy.The PTO shaft 16 here is brought into its stopped state by the operationof the transmission 5.

As discussed above, the operation of the PTO switch 23 also makes itpossible to drive or stop the PTO shaft 16. Therefore, the automaticsteering during rearward travel may be allowed or prohibited based onthe position of the PTO switch 23 instead of the position of the PTOspeed change lever 24. Specifically, for example, in step T1 in FIG. 9 ,the state of the PTO switch 23 may be detected instead of the PTO speedchange lever 24, and in step T2 in FIG. 9 , whether the PTO switch 23 isin the neutral position Qx or not may be determined. The PTO speedchange lever 24 may be, for example, a shift lever or a select leverswingable forward and rearward and leftward and rightward or the like.

In the foregoing preferred embodiment, the switch box 19 (FIG. 7 )attachable at a location rearward of the operator's seat 10 (locationdownstream of the operator's seat 10 in the rearward direction A2) isprovided with the steering switch 54 as a manual operator for automaticsteering. Note, however, that this does not imply any limitation. Forexample, as illustrated in FIG. 11 , the switch box 19 may be providedwith a correction switch 63 as a manual operator for automatic steering.The correction switch 63 has the same functions as the correction switch53 (FIG. 6 ) provided on the console 9F. The functions of a leftcorrection key 63L and a right correction key 63R of the correctionswitch 63 are the same as those of the left correction key 53L and theright correction key 53R of the correction switch 53. Such aconfiguration make it possible, during automatic steering duringrearward travel of the vehicle body 3, for the operator to operate thecorrection key(s) 63L and/or 63R to correct the position of the vehiclebody 3 detected by the position detector 40 while looking back (whilefacing in the rearward direction A2). During automatic steering, thecontroller 60 may, once one of the correction switches 53 and 63 hasbeen operated, disable the other of the correction switches 53 and 63until the automatic steering ends.

Other manual operator(s) for automatic steering such as the mode switch50 and/or the defining switch 51 may be provided on at least one of theconsoles 9F, 9L, and 9R located forward of the operator's seat 10(located downstream of the operator's seat 10 in the forward directionA1) and on opposite sides of the operator's seat 10, and on the switchbox 19 attachable at a location rearward of the operator's seat 10(attachable at a location downstream of the operator's seat 10 in therearward direction A2). The manual operator(s) for automatic steeringis/are not limited to push switch(es), and may be switch(es) ofdifferent types such as slide switch(es) and/or tumbler switch(es),key(s) and/or lever(s) other than switches, and/or the like.

A working vehicle 1 according to one or more preferred embodimentsachieves the following effects.

A working vehicle 1 according to one or more preferred embodimentsincludes a vehicle body 3 to be manually steered with a steering wheel30 or automatically steered to travel forward or rearward, an operator'sseat 10 on the vehicle body 3, a console 9F, 9L, 9R located forward ofthe operator's seat 10 or located on one side of the operator's seat 10,a first manual operator 50, 51, 52, 53 for automatic steering providedin or on the console 9F, and a second manual operator 54, 63 forautomatic steering attachable at a location rearward of the operator'sseat 10.

The above configuration makes it possible, when automatic steering isperformed during forward travel of the vehicle body 3 of the workingvehicle 1, to operate the first manual operator 50, 51, 52, 53 forautomatic steering located forward of the operator's seat 10 or the likeand, when automatic steering is performed during rearward travel of thevehicle body 3, to operate the second manual operator 54, 63 forautomatic steering located rearward of the operator's seat 10. Thiseliminates the need for the operator to move the manual operator 50, 51,52, 53, 54, 63 for automatic steering according to the direction oftravel of the vehicle body 3 when performing the automatic steering,making it possible to reduce complexity of operation.

In one or more preferred embodiments, the first manual operator 50, 51,52, 53 and the second manual operator 54, 63 may include respectivesteering switches 52, 54 to be operated to issue an instruction to startor stop the automatic steering. With this, the steering switch 52located forward of the operator's seat 10 is operated to start or stopautomatic steering when automatic steering is performed during forwardtravel of the vehicle body 3, whereas the steering switch 54 locatedrearward of the operator's seat 10 is operated to start or stopautomatic steering when automatic steering is performed during rearwardtravel of the vehicle body 3, thus improving ease of operation.

In one or more preferred embodiments, the working vehicle 1 may furtherinclude a position detector 40 to detect a position of the vehicle body3. The first manual operator 50, 51, 52, 53 may include a definingswitch 51 to be operated to issue an instruction to define a referencetravel line L1 based on which the automatic steering is performed, and acorrection switch 53 to be operated to issue an instruction to correctthe position of the vehicle body 3 detected by the position detector 40,or the first manual operator 50, 51, 52, 53 and the second manualoperator 54, 63 may include respective defining switches 51 to beoperated to issue an instruction to define a reference travel line L1based on which the automatic steering is performed, and respectivecorrection switches 53, 63 to be operated to issue an instruction tocorrect the position of the vehicle body 3 detected by the positiondetector 40. This makes it possible to define a reference travel line L1by operating the defining switch 51 and then perform automatic steeringby operating the steering switch 52 or 54 according to the direction oftravel of the vehicle body 3. It is also possible to operate thecorrection switch 53 during automatic steering to correct the positionof the vehicle body 3 detected by the position detector 40 toappropriately perform the automatic steering.

In the preferred embodiment as illustrated in FIG. 11 , the secondmanual operator 54, 63 may include a correction switch 63 to be operatedto issue an instruction to correct the position of the vehicle body 3detected by the position detector 40. This makes it possible to correctthe position of the vehicle body 3 detected by the position detector 40by operating the correction switch 53 or 63 corresponding to thedirection of travel of the vehicle body 3 to appropriately performautomatic steering, and possible to further reduce complexity of theoperator's operation.

In one or more preferred embodiments, the working vehicle 1 may furtherinclude a controller 60 to control the automatic steering. Thecontroller 60 may be configured or programmed to define, upon operationof the defining switch 51 or one of the defining switches 51 at a startand end of travel of the vehicle body 3 in which the vehicle body 3 ismanually steered, the reference travel line L1 based on positions of thevehicle body 3 detected by the position detector 40, start the automaticsteering upon operation of one of the steering switches 52, 54 to startthe automatic steering, stop the automatic steering upon operation ofone of the steering switches 52, 54 to stop the automatic steering,correct a position of the vehicle body 3 upon operation of thecorrection switch 53, 63 or one of the correction switches 53, 63, andupon operation of one of the respective switches (steering switches 52and 54 or correction switches 53 and 63) of the first manual operator50, 51, 52, 53 and the second manual operator 54, 63 having the samefunction, disable the other of the switches until the automatic steeringends.

This makes it possible to appropriately perform automatic steeringduring forward or rearward travel of the vehicle body 3. It is alsopossible to eliminate or reduce the likelihood that, when one of thesteering switches 52 and 54 having the same function is operated tostart automatic steering or when one of the correction switches 53 and63 having the same function is operated to correct the position of thevehicle body 3, the other of the switches will be accidentally operatedto stop automatic steering or correct the position of the vehicle body 3without the operator's intention, making it possible to ensure safety.

In one or more preferred embodiments, the second manual operator 54 maybe electrically connected to the controller 60 by an electric wire 74routed from the location rearward of the operator's seat 10 to theconsole 9F through a side portion of the vehicle body 3. This allows aninput signal corresponding to the operation of the second manualoperator 54 to be transmitted from the second manual operator 54 via theelectric wire 74 to the controller 60, making it possible to performautomatic steering according to the operation of the second manualoperator 54.

In one or more preferred embodiments, the working vehicle 1 may furtherinclude a protection structure 6 to protect the operator's seat 10. Thesecond manual operator 54, 63 may be attachable to and detachable fromthe protection structure 6. This allows the operator to attach thesecond manual operator 54, 63 to a desired position on the protectionstructure 6, making it possible to improve ease of operation of thesecond manual operator 54, 63.

In one or more preferred embodiments, the protection structure 6 mayinclude pillars 6L and 6R extending upward from a left rear portion anda right rear portion of the vehicle body 3, respectively, and a beam 6 bconnecting upper ends of the pillars 6L and 6R. The second manualoperator 54, 63 may include a housing (switch box) 19 attachable to anddetachable from any of the pillars 6L and 6R, and an operable key 54 a,54 a, 63L, 63R provided on a surface (front surface) 19 f of the housing19 other than a mount surface 19 b for contact with the pillar 6L.

This makes it possible to eliminate or reduce the likelihood that, whenthe operator looks back (looks in the rearward direction A2) to ensuresafety when performing automatic steering during rearward travel of thevehicle body 3, the field of vision of the operator will be narrowed bythe protection structure 6 and/or the second manual operator 54, 63. Itis also possible for the operator looking back (looking in the rearwarddirection A2) to visually recognize the key(s) 54 a, 54 b, 63L, 63R ofthe second manual operator 54, 63 while ensuring safety behind theworking vehicle 1 (area downstream of the working vehicle 1 in therearward direction A2), making it possible to improve ease of operationof the key 54 a, 54 b, 63L, 63R.

In one or more preferred embodiments, the working vehicle 1 may furtherinclude a falling preventer 57 to prevent the second manual operator 54from falling out of the protection structure 6. This makes it possibleto eliminate or reduce the likelihood that the second manual operator 54will come off the protection structure 6 due to vibrations from theworking vehicle 1 and be damaged or lost.

A working vehicle 1 according to one or more preferred embodimentsincludes a vehicle body 3 to be manually steered with a steering wheel30 or automatically steered to travel forward or rearward, a prime mover4 on the vehicle body 3, a working implement 2 supported on the vehiclebody 3, a power take-off (PTO) 16 shaft to transmit power from the primemover 4 to the working implement 2, and a controller 60 to controlautomatic steering of the vehicle body 3 and driving of the PTO shaft16, wherein the controller 60 is configured or programmed to allow theautomatic steering during rearward travel of the vehicle body 3 when thePTO shaft 16 is in a stopped state, and prohibit the automatic steeringduring rearward travel of the vehicle body 3 when the PTO shaft 16 is ina driven state.

With the above configuration of the working vehicle 1, automaticsteering during rearward travel is performed while the PTO shaft 16 isin the stopped state, whereas the automatic steering during rearwardtravel is not performed while the PTO shaft 16 is in the driven state.This makes it possible to stably and safely perform automatic steeringduring rearward travel.

In one or more preferred embodiments, the working vehicle 1 may furtherinclude a PTO operation actuator 24, 23 (PTO speed change lever 24, PTOswitch 23) to control the driving of the PTO shaft 16 and to be movedfrom a neutral position Qn, Qx to a driving position Q1, Q2, Q3, Qb, Qz.When the PTO operation actuator 24, 23 is in the neutral position Qn,Qx, the PTO shaft 16 is in the stopped state and the controller 60allows the automatic steering during rearward travel of the vehicle body3. Upon movement of the PTO operation actuator 24, 23 to the drivingposition Q1, Q2, Q3, Qb, Qz, the controller 60 prohibits the automaticsteering during rearward travel of the vehicle body 3 and the PTO shaft16 is allowed to be driven.

With the above configuration, upon movement of the PTO operationactuator 24, 23 to a driving position Q1, Q2, Q3, Qb, Qz to drive thePTO shaft 16, automatic steering during rearward travel is disallowed.When the PTO operation actuator 24, 23 is in the neutral position Qn, Qxand the PTO shaft 16 is in the stopped state, automatic steering duringrearward travel is allowed. This makes it possible to stably and safelyperform automatic steering during rearward travel of the working vehicle1.

In one or more preferred embodiments, the working vehicle 1 may furtherinclude a position detector 40 to detect a position of the vehicle body3, a defining switch 51 to be operated to issue an instruction to definea reference travel line L1 based on which the automatic steering isperformed, and a steering switch 52, 54 to be operated to issue aninstruction to start or stop the automatic steering. The controller 60may be configured or programmed to define the reference travel line L1in response to an operation of the defining switch 51 based on positionsof the vehicle body 3 that were detected by the position detector 40while the vehicle body 3 was manually steered to travel. The controller60 may be configured or programmed to, if the automatic steering duringrearward travel of the vehicle body 3 is allowed, start the automaticsteering in response to an operation of the steering switch 52, 54 tostart the automatic steering, perform the automatic steering based onthe reference travel line L1 and on the position of the vehicle body 3detected by the position detector 40, and stop the automatic steering inresponse to an operation of the steering switch 52, 54 to stop theautomatic steering. The controller 60 may be configured or programmedto, if the automatic steering during the rearward travel of the vehiclebody 3 is prohibited, not start or stop the automatic steering inresponse to the operation of the steering switch 52, 54.

With the above configuration, by operating the defining switch 51 andthe steering switch 52, 54, it is possible to reliably and stablyperform automatic steering during rearward travel of the working vehicle1. It is also possible to ensure safety, because the automatic steeringduring rearward travel is not started while it is prohibited even if thesteering switch 52, 54 is operated to start the automatic steering.

In one or more preferred embodiments, the working vehicle 1 may furtherinclude a notifier (display) 45 to provide a notification indicatingthat the automatic steering during rearward travel of the vehicle body 3is prohibited. This makes it possible to eliminate or reduce thelikelihood that, when the automatic steering during rearward travel ofthe working vehicle 1 is prohibited and the automatic steering is notperformed, the operator of the working vehicle 1 will mistakenly believethat the working vehicle 1 is broken.

In one or more preferred embodiments, the notifier 45 may be operable tofurther provide a notification including guidance which is a prompt forthe PTO shaft 16 to be stopped. This makes it possible for the operatorof the working vehicle 1 to recognize that automatic steering duringrearward travel is prohibited because the PTO shaft 16 is in the drivenstate and that the automatic steering during rearward travel will beallowed when the PTO shaft 16 is stopped.

In one or more preferred embodiments, the notifier 45 may be operable toprovide the notification when an instruction to start the automaticsteering is issued, if the automatic steering during rearward travel ofthe vehicle body 3 is prohibited. This allows the operator to recognizethat, for example, automatic steering during rearward travel isprohibited and/or that the prohibition is because of the PTO shaft 16 inthe driven state, when the operator wishes to start the automaticsteering of the working vehicle 1. It is also possible to reduce thefrequency of notifications by the notifier 45, making it possible toeliminate or reduce the likelihood that the operator will be overwhelmedby the notifications and to reduce power consumption.

While preferred embodiments of the present invention have been describedabove, it is to be understood that variations and modifications will beapparent to those skilled in the art without departing from the scopeand spirit of the present invention. The scope of the present invention,therefore, is to be determined solely by the following claims.

What is claimed is:
 1. A working vehicle comprising: a vehicle body tobe manually steered with a steering wheel or automatically steered totravel forward or rearward; an operator's seat on the vehicle body; aconsole located forward of the operator's seat or located on one side ofthe operator's seat; a first manual operator for automatic steeringprovided in or on the console; and a second manual operator forautomatic steering attachable at a location rearward of the operator'sseat.
 2. The working vehicle according to claim 1, wherein the firstmanual operator and the second manual operator include respectivesteering switches to be operated to issue an instruction to start orstop the automatic steering.
 3. The working vehicle according to claim2, further comprising: a position detector to detect a position of thevehicle body; wherein the first manual operator includes: a firstdefining switch to be operated to issue an instruction to define areference travel line based on which the automatic steering isperformed; and a first correction switch to be operated to issue aninstruction to correct the position of the vehicle body detected by theposition detector; or the first manual operator and the second manualoperator include: respective defining switches to be operated to issuean instruction to define a reference travel line based on which theautomatic steering is performed; and respective correction switches tobe operated to issue an instruction to correct the position of thevehicle body detected by the position detector.
 4. The working vehicleaccording to claim 3, further comprising: a controller to control theautomatic steering, wherein: the controller is configured or programmedto: define, upon operation of the first defining switch or one of therespective defining switches at a start and end of travel of the vehiclebody in which the vehicle body is manually steered, the reference travelline based on positions of the vehicle body detected by the positiondetector; start the automatic steering upon operation of one of therespective steering switches to start the automatic steering; stop theautomatic steering upon operation of one of the respective steeringswitches to stop the automatic steering; correct a position of thevehicle body upon operation of the first correction switch or one of therespective correction switches; and upon operation of one of therespective switches of the first manual operator and the second manualoperator having a same function, disable another of the respectiveswitches of the first manual operator and the second manual operatoruntil the automatic steering ends.
 5. The working vehicle according toclaim 4, wherein the second manual operator is electrically connected tothe controller by an electric wire routed from the location rearward ofthe operator's seat to the console through a side portion of the vehiclebody.
 6. The working vehicle according to claim 1, further comprising: aprotection structure to protect the operator's seat; wherein the secondmanual operator is attachable to and detachable from the protectionstructure.
 7. The working vehicle according to claim 6, wherein: theprotection structure includes: pillars extending upward from a left rearportion and a right rear portion of the vehicle body, respectively; anda beam connecting upper ends of the pillars; and the second manualoperator includes: a housing attachable to and detachable from any ofthe pillars; and an operable key provided on a surface of the housingother than a mount surface for contact with the pillar.
 8. The workingvehicle according to claim 6, further comprising a falling preventer toprevent the second manual operator from falling out of the protectionstructure.
 9. The working vehicle according to claim 7, furthercomprising a falling preventer to prevent the second manual operatorfrom falling out of the protection structure.
 10. The working vehicleaccording to claim 2, further comprising: a protection structure toprotect the operator's seat; wherein the second manual operator isattachable to and detachable from the protection structure.
 11. Theworking vehicle according to claim 10, wherein: the protection structureincludes: pillars extending upward from a left rear portion and a rightrear portion of the vehicle body, respectively; and a beam connectingupper ends of the pillars; and the second manual operator includes: ahousing attachable to and detachable from any of the pillars; and anoperable key provided on a surface of the housing other than a mountsurface for contact with the pillar.
 12. The working vehicle accordingto claim 10, further comprising a falling preventer to prevent thesecond manual operator from falling out of the protection structure. 13.The working vehicle according to claim 11, further comprising a fallingpreventer to prevent the second manual operator from falling out of theprotection structure.
 14. The working vehicle according to claim 3,further comprising: a protection structure to protect the operator'sseat; wherein the second manual operator is attachable to and detachablefrom the protection structure.
 15. The working vehicle according toclaim 14, wherein: the protection structure includes: pillars extendingupward from a left rear portion and a right rear portion of the vehiclebody, respectively; and a beam connecting upper ends of the pillars; andthe second manual operator includes: a housing attachable to anddetachable from any of the pillars; and an operable key provided on asurface of the housing other than a mount surface for contact with thepillar.
 16. The working vehicle according to claim 14, furthercomprising a falling preventer to prevent the second manual operatorfrom falling out of the protection structure.
 17. The working vehicleaccording to claim 15, further comprising a falling preventer to preventthe second manual operator from falling out of the protection structure.18. The working vehicle according to claim 4, further comprising: aprotection structure to protect the operator's seat; wherein the secondmanual operator is attachable to and detachable from the protectionstructure.
 19. The working vehicle according to claim 18, wherein: theprotection structure includes: pillars extending upward from a left rearportion and a right rear portion of the vehicle body, respectively; anda beam connecting upper ends of the pillars; and the second manualoperator includes: a housing attachable to and detachable from any ofthe pillars; and an operable key provided on a surface of the housingother than a mount surface for contact with the pillar.
 20. The workingvehicle according to claim 18, further comprising a falling preventer toprevent the second manual operator from falling out of the protectionstructure.